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authorChris Mason2007-11-27 01:34:41 +0100
committerChris Mason2008-09-25 17:03:58 +0200
commit793955bca66c99defdffc857ae6eb7e8431d6bbe (patch)
tree2f8376247033fced7289038b8d82e10a6cc55f22 /fs/btrfs/disk-io.c
parentBtrfs: Handle writeback under high memory pressure better (diff)
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Btrfs: Limit btree writeback to prevent seeks
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/disk-io.c')
-rw-r--r--fs/btrfs/disk-io.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 3e16cca72b49..28e9ef8a3253 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -210,6 +210,15 @@ static int btree_writepages(struct address_space *mapping,
{
struct extent_map_tree *tree;
tree = &BTRFS_I(mapping->host)->extent_tree;
+ if (wbc->sync_mode == WB_SYNC_NONE) {
+ u64 num_dirty;
+ u64 start = 0;
+ unsigned long thresh = 96 * 1024 * 1024;
+ num_dirty = count_range_bits(tree, &start, thresh, EXTENT_DIRTY);
+ if (num_dirty < thresh) {
+ return 0;
+ }
+ }
return extent_writepages(tree, mapping, btree_get_extent, wbc);
}